"TITLE","AUTHORS","SUBJECT","SUBJECT_RELATED","DESCRIPTION","PUBLISHER","AVAILABILITY","RESEARCH_ORG","SPONSORING_ORG","PUBLICATION_COUNTRY","PUBLICATION_DATE","CONTRIBUTING_ORGS","LANGUAGE","RESOURCE_TYPE","TYPE_QUALIFIER","JOURNAL_ISSUE","JOURNAL_VOLUME","RELATION","COVERAGE","FORMAT","IDENTIFIER","REPORT_NUMBER","DOE_CONTRACT_NUMBER","OTHER_IDENTIFIER","DOI","RIGHTS","ENTRY_DATE","OSTI_IDENTIFIER","PURL_URL" "Microbiological Studies on the Influence of Combined Processes of Heat and Irradiation on the Survival of Saccharomyces Cerevisiae Var. Ellipsoideus; Etudes Microbiologiques sur l'Influence d'un Traitement Mixte par Chauffage et Irradiation sur la Survie de Saccharomyces Cerevisiae Var. Ellipsoideus; Mikrobiologicheskie issledovaniya vliyaniya sovmestnykh protsessov nagreva i oblucheniya na vyzhivanie saccharomyces Cerevisiae Var. Ellipsoideus; Estudios Microbiologicos de la Influencia del Calentamiento e Irradiacion Combinados Sobre la Supervivencia del Saccharomyces Cerevisiae Var. Ellipsoideus","Stehlik, G.; Kaindl, K. [Institute for Biology and Agriculture, Reaktorzentrum, Seibersdorf (Austria)]","61 RADIATION PROTECTION AND DOSIMETRY; APPLES; COBALT 60; COLONY FORMATION; COMPARATIVE EVALUATIONS; GAMMA RADIATION; GLASS; GRAPES; HEAT; HEAT TREATMENTS; HEATING; IRRADIATION; NUTRIENTS; RADIATION DOSE UNITS; RADIATION DOSES; SACCHAROMYCES CEREVISIAE; STRAINS; SURVIVAL CURVES","","In the framework of the Seibersdorf International Programme on Irradiation Preservation of Fruit and Fruit Juices one of the main items of research deals with the problem of the radiosensitization of microorganisms. To study the effect of heat and irradiation treatments on the survival of yeast cells (colony formation), a highly radioresistant strain, Saccharomyces cerevisiae var. ellipsoideus, grown in a semi-synthetic nutrient medium, was given a combined treatment of heating and gamma irradiation ({sup 60}Co source) at the beginning of its log phase. The heat treatment was applied either immediately before, during or immediately after the irradiation process. The temperature was varied between 20 Degree-Sign C and 52.5 Degree-Sign C. The irradiation treatment was carried out with a dose range of up to 0.3 x 10{sup 6} rad in a well-aired glass tube. The inhibiting effect of this combined treatment depends upon the sequence of heating and irradiation and shows the following results: the most effective combination is the simultaneous treatment of heating and irradiation; less effective is this combination wherein irradiation at room temperature follows the heating procedure; and most ineffective is the heating after irradiation at room temperature. The combined heat/irradiation treatment results in survival curves (survival fractions) which are straight lines in relation to the irradiation dose at a semi-logarithmic scale in the temperature range between room temperature and 45 Degree-Sign C. Above 45 Degree-Sign C the curves show, at doses lower than 30 krad, an increase of the survivals compared with the unirradiated sample. By comparing the slopes of the survival curves obtained at different temperatures, one can see that in the case of irradiation at temperatures higher than 40 Degree-Sign C there is a high synergistic effect for the simultaneous treatment, e.g. about 2 orders of magnitude at 150 krad. Based on these results the technological possibilities of this treatment are under investigation on apple and grape juice. (author) [French] L'un des principaux sujets de recherche inscrits au programme international sur la conservation des fruits et jus de fruits par irradiation, execute a Seibersdorf, est le probleme de la radiosensibilisation des micro-organismes. En vue d'etudier l'effet d'un traitement par la chaleur et l'irradiation sur la survie des cellules de levures (formation de colonies), une souche a forte radioresistance - Saccharomyces cerevisiae var. ellipsoideus - cultivee sur un milieu nutritif semi-synthetique, a ete soumise des le debut de sa phase logarithmique a un traitement combine par chauffage et irradiation gamma (source au cobalt-60). Le traitement thermique a ete applique, soit immediatement avant l'irradiation, soit pendant ou immediatement apres celle-ci. On a fait varier la temperature entre 20 et 52,5 Degree-Sign C. Pour l'irradiation, effectuee dans Bullet un tube en verre bien aere, on a utilise des doses allant jusqu'a 0, 3 x 10{sup 6} rad. L'effet d'inhibition de ce traitement mixte depend de l'ordre de succession du chauffage et de l'irradiation; les resultats obtenus sont les suivants: la combinaison la plus efficace est un traitement simultane par chauffage et irradiation; la combinaison qui consiste a faire suivre le chauffage d'une irradiation a la temperature ambiante est moins efficace; le moindre effet a ete obtenu par chauffage apres irradiation a la temperature ambiante. Le traitement mixte chaleur/irradiation donne des courbes de survie (fractions d'organismes survivants) qui sont des lignes droites ayant pour coordonnees la dose d'irradiation a une echelle semi-logarithimique, et la temperature dans l'intervalle compris entre la temperature ambiante et 45 Degree-Sign C. Au-dessus de 45 Degree-Sign C, les courbes indiquent, a des doses inferieures a 30 krad, un accroissement du nombre des survivants par rapport a l'echantillon non irradie. En comparant les pentes des courbes de survie obtenues a des temperatures differentes, on constate que, dans le cas d'une irradiation a une temperature superieure a 40 Degree-Sign C, le traitement simultane produit un effet synergique prononce, qui atteint deux ordres de grandeur pour 150 krad. En partant de ces resultats, on procede actuellement a une etude des possibilites techniques de ce traitement sur des jus de pomme et de raisin. (author) [Spanish] Uno de los principales temas de investigacion incluidos en el programa internacional relativo a la irradiacion de frutas y zumos de fruta que se viene ejecutando en Seibersdorf se refiere al problema de la radio- sensibilizacion de microorganismos. Para estudiar los efectos del tratamiento termico y del tratamiento por irradiacion sobre la supervivencia de las celulas de levadura (formacion de colonias), se sometio a un tratamiento combinado de aplicacion de calor y de irradiacion gamma (fuente: {sup 60}Co), al comienzo de su fase de desarrollo logaritmico, una cepa de elevada radiorresistencia -Saccharomyces cerevisiae var. ellipsoideus - cultivada en un medio nutritivo semisintetico. El calor se aplico inmediatamente antes de la irradiacion, durante esta o inmediatamente despues. Las temperaturas estuvieron comprendidas entre 20 y 52,5 Degree-Sign C. La irradiacion se realizo con dosis de hasta 0,3 x 10{sup 6} rad, en un tubo de vidrio, bien aireado. El efecto inhibidor de este tratamiento combinado depende del orden en que se suceden la aplicacion del calor y la irradiacion, habiendose llegado a las siguientes conclusiones: la combinacion mas eficaz consiste en simultanear el tratamiento termico con el tratamiento por irradiacion; esta combinacion resulta menos eficaz cuando la irradiacion a la temperatura ambiente tiene lugar a continuacion del tratamiento termico; la combinacion de eficacia minima consiste en proceder al tratamiento termico despues de haberse efectuado la irradiacion a la temperatura ambiente. El tratamiento termico combinado con la irradiacion se traduce en un grafico de supervivencia (fracciones de supervivencia) que presenta la forma de linea recta en funcion de la dosis de irradiacion en una escala semilogantmica para el intervalo de temperaturas comprendido entre la temperatura ambiente y 45 Degree-Sign C. Por encima de los 45 Degree-Sign C las lineas revelan un aumento de las supervivencias, en comparacion con la muestra no irradiada, para dosis inferiores a 30 krad. Comparando las pendientes de las lineas de supervivencia obtenidas a distintas temperaturas, puede observarse que en el caso de una irradiacion a temperaturas superiores a 40 Degree-Sign C se produce un acusado efecto. (author) [Russian] V ramkah mezhdunarodnoj programmy Zajbersdorfskoj laboratorii po oblucheniju fruktov i fruktovyh sokov s cel'ju ih sohranenija odnim iz naibolee vazhnyh issledovanij javljaetsja radiacionnaja sensibilizacija mikroorganizmov. Dlja izuchenija vlijanija termicheskoj obra tki i obluchenija na vyzhivanie drozhzhevyh kletok (obrazovanie kolonii) vysokoustojchivaja k radiacii raznovidnost' Saccharomyces cerevisiae var. ellipsoideus, vyrashhennaja v polusinteticheskoj pitatel'noj srede, podvergalas' v nachale log-fazy svoego razvitija kombinirovannoj obrabotke nagrevom i gamma-oblucheniem (istochnik - kobal't-60). Nagrev proizvodilsja ili neposredstvenno pered processom obluchenija, ili odnovremenno s nim, ili posle nego. Temperatura menjalas' ot 20 do 52,5 Degree-Sign C. Obluchenie velos' v horosho produtoj vozduhom stekljannoj trubke v intervale doz do 0,3 x 10{sup 6} rad. Ingibirujushee vlijanie takoj obrabotki zavisit ot posledovatel'nosti nagreva i obluchenija. Bylo ustanovleno sledujushhee: naibolee jeffektivnym javljaetsja odnovremennoe provedenie nagreva i obluchenija; menee jeffektivnym javljaetsja obluchenie pri komnatnoj temperature posle nagreva; naimenee jeffektivnym okazalsja nagrev posle obluchenija pri komnatnoj temperature. V rezul'tate kombinirovannoj termicheskoj i radiacionnoj obrabotki byli sostavleny grafiki vyzhivanija (frakcii vyzhivanija), predstavljajushhie soboj prjamye linii otnositel'no doz radiacii v polulogarifmicheskom masshtabe v intervale temperatur ot komnatnoj do 45 Degree-Sign C. Pri temperature vyshe 45 Degree-Sign C v dozah menee 30 krad grafiki pokazyvajut uvelichenie vyzhivaemosti po sravneniju s neobluchennymi obrazcami. Sravnivaja naklon krivyh vyzhivanija, poluchennyh pri razlichnyh temperaturah, mozhno zametit', chto pri obluchenii pri temperaturah vypce 40 Degree-Sign C nabljudaetsja sil'nyj sinjergeti - cheskij jeffekt, naprimer na dva porjadka pri 150 krad. Na osnovanii poluchennyh rezul'tatov sejchas izuchajutsja tehnologicheskie vozmozhnosti takoj obrabotki jablochnyh i vinogradnyh sokov. (author)","IAEA; Vienna (International Atomic Energy Agency (IAEA))","","International Atomic Energy Agency, Vienna (Austria); Food and Agricultural Organization of the United Nations, Rome (Italy)","","IAEA","1966-11-15","","English","Conference","Conference","","","Conference: International Symposium on Food Irradiation, Karlsruhe, Federal Republic of Germany (Germany), 6-10 Jun 1966; Other Information: 4 refs., 3 figs.; Related Information: In: Food Irradiation. Proceedings of the International Symposium on Food Irradiation| 979 p.","","Medium: X; Size: page(s) 299-305","ISSN 0074-1884","IAEA-SM-73/43","","Other: ISSN 0074-1884; TRN: XA13M2042075514","https://doi.org/","","2013-09-05","22118878",""